In response to an updated question: I recommend reading the Microsoft advisor . It gives a good overview of the five main parameters (transfer, renew, rewrite, replace, do nothing). You need to think about the pros and cons of each option and how important they are to you. There is no answer to this question on one size.
Switching to .Net using Visual Studio 2008..NET 3.5 objects and gives you a dependency on Microsoft.VisualBasic.Compatibility.dll ( VisualBasic.Compatibility namespace). This has been deprecated in .Net 4, so it can be dropped in a future version .Net. This is an argument in favor of commercial migration or rewriting tools.
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